Differentiation of tin oxides using electron energy-loss spectroscopy

Abstract

We have used electron energy-loss spectroscopy to search for differences in the energy-loss near-edge structure of SnO, ${\text{SnO}}_{2}$, and an intermediate oxide, with a view to distinguishing them unambigously. We have found that the oxygen $K$ edge exhibits clear differences that can be used for fingerprinting each phase. The oxygen edge appears at the same position for each phase whereas a chemical shift of the Sn ${M}_{4,5}$ edge of about $3.5\phantom{\rule{0.3em}{0ex}}\text{eV}$ was observed between phases with Sn in $2+$ and $4+$ oxidation states. Both observations can be used to distinguish between the three phases, allowing their on-line identification within nanostructured materials.